1923 B3 'Charlotte II' in 1:3 Scale

[ARUP]

The fin is done! The fuselage was needed to get it properly sized. Considering thicknesses added for sheeting of the fuselage, the vertical fin post was clamped to the vertical on the fuselage. The horizontal member of the fin was 'gusseted' to the fin post. After glue dried this was removed from fuselage then finished on the plan. All the cross members will get pinned to the outer perimeter using toothpicks and the gusset will get cut away. here is the fin on the fuselage. The mounting points will get fabricated next.

[lenb]

That's one of the cooler looking designs you've done..
Should be a trip to see it in the air.

[ingrahal]

I agree it's nearly a flying wing

[ARUP]

Yeah... it's definitely a 'bat' looking plank type wing! Metal fittings and hard points made to connect fin to fuselage. Two fittings are captured by the fin so that it can be secured to fuselage. The wood that captures the fittings allows fabric to attach, also. The last fitting is some kind of fuselage 'strengther'.

[ARUP]

Did more work today. Two large gussets were put inside cabin area after putting 1/16" marine ply on bottom of fuselage. The gusset on the door side will act as a 'stop' to keep the door from swinging inward too far. The forward part of the fuselage needed to be strengthened somewhat, I suppose. I stained the inside of the fuselage, too, using H.Behlen's Medium Brown Walnut color. It is water based so won't affect glue joints! I made sure that all wood was stained if it could be visualized from the cockpit opening or doorway. Two sheets of 1/64" ply got stained in preparation for covering the fuselage. Gussets were added so that ply from the cockpit opening to the rear of fuselage where the center pylon meets top fuselage longeron could be laid fair. There are some oddly curved intersections there. The rest of the fuselage will be pretty straightforward. The tow release needs to be installed. I'm saving a small piece of marine ply installation at the bottom of the nose area for last so that some lead can be hidden inside the balsa block on the nose. Lastly, the skid and its mounting points still needs to be fabricated.

[lenb]

Cruising along now Michael, I hope we can fly this in June.

[ARUP]

Len, I'd like to have it ready for SERA because it would be an awesome venue for the maiden. I've been busy. The tow release is getting fabricated and installed and the first and most difficult pieces of ply were put on this morning. When more ply goes on I'll get more pics. I have continuing education Thursday, Friday, Saturday and Sunday so won't get a whole lot done this weekend.

[Melchizedek]

Looking great as always Michael. Your birds are works of art.

Kevin

[ARUP]

Hey Kevin... thanks for dropping by and thanks for the compliment! I hope you build a sailplane for aerotow soon. Man, it is so fun! I sure wish I could have this ready for SERA but no way. That huge field would be perfect for first flights. The first bit of ply covering has gone onto the fuselage. Do the hard bits first to make the others seem super easy. The most difficult piece was just at the TE section pf fuselage. It has a bit of a compound curve so the ply was wetted and gently formed into the groove it lay. It was allowed to dry without glue by clamping it in place using some custom fitted balsa blocks. Once dry the ply was taken off then glued back in place. While the glue was drying the tow release parts were fabricated. A wire hoop was made from music wire, painted and epoxied into the nose. CF tow was epoxied around the area to strengthen everything. A Hitec 625MG servo was fitted and mounts made to support it at the appropriate height and angle. I made sure to activate the servo via the transmitter to get proper throws.









Some of the pics are a little fuzzy. The release pin was heated and hammered flat on one end so it could be drilled to receive a link from the servo. This articulation is needed so binding doesn't occur. The link has a clevis on the servo end but I put a 'Z' bend at the other end in lieu of soldering another clevis. There is no picture of the link but I can get one if the wordage doesn't make sense and you are interested. The pin is slides inside a brass tube which was solidly mounted on the same 'plate' that the wire loop attaches.

[ARUP]

The scale door was framed into the fuselage. Temporary 1/64" spacers were set into the jambs while building the door frame. The ply skin was put onto the door while it was still in situ. That way no twists would be built into the door. The ply overlaps the opening a little on all but the hinge edge. A latch and catch were fabricated to make the door secure when closed but easy to open from the cockpit opening. I haven't a clue how the full scale item was done. Yayyyy for artistic license, right?! I may change the release handle mechanism because I don't like the way the handle wrapped with a cable looks. Yes, Virginia, I have too much time on my hands! I used scrap phenolic, wood, screws, cable, aluminum tubing and a spring to make this. It's fun! Oh... the DuBro hinges were darkend with a black Sharpie to resemble blackened brass hinges. The triangle gusset mentioned in a previous post acts as a door stop and another smaller one was put in the upper corner.







More....

[ARUP]

Ply was soaked in hot water then partially wrapped around a form (cardboard tube, ) and allowed to dry while gently clamped. Don't ever use ammonia to bend wood unless you don't care about it becoming brittle and structurally useless! Once the ply skin was dry it was fitted and cut to the proper shape for the nose portion of the fuselage. Lots of trial and error along with a card stock pattern were needed for this but once both halves are in place the rest will be easy. I had to add an extra fuselage former to support the ply to keep it from 'oil canning' The naked balsa (picture) was stained to match. Remember: do the difficult parts first. The reason I did the ply skin for the nose this way is that photographic evidence supports this method. The full scale has a seam down the middle of the nose and little brads or tiny nail heads can be seen on both sides of the join line. There must have been a cleat behind the ply in this location. It would have been easier to just wrap the ply around the nose from one side to the other but it would not look proper from a wood grain perspective.





That's it for now! Has everyone picked their favorite horse for the Kentucky Derby? It's this weekend! Fix yourself a Mint Julep, too! The sugar water goes on the bottom in the julep cup with crushed ice and the bourbon floats on top. Use the straw to sip a little sugar water then a little bourbon (not whiskey), swish in your mouth and notice the aroma of the sprig of mint in the glass! Mmmmmmmm!

[Dion Dunn]

Looks good Michael! How many cans of that color stain do you own?

FWIW, I like the Old Forester pre-mix mint julep.

[ARUP]

Dion... believe it or not it is the same bottle of stain used on previous projects! It is very dark but has great tone so I mix it with water ~50% to lighten it up a bit. I will need to get another soon, though. Glad you like the pre-mix. I still do it the old fashioned way just like with the models I like to build. I have a stand of mint growing in my back yard! Comes in very handy for iced tea, mint juleps and such!!!

I changed the release handle portion of the door latch mechanism. It now has a wooden knob mounted to a music wire segment. The wire is connected to a 'walking beam' affair. I made a hand turn drill bit from a piece of scrap 1/2" copper pipe by cutting serrations into its edge with a Dremel cut-off wheel. Plugs of balsa were removed from a balsa block and a long plug of balsa was removed from the nose of the fuselage. The balsa block was pinned to a balsa sheet base. Lead was melted then poured into the block. After the lead slugs cooled they were removed from the block, cleaned of 'charcoal', planished smooth using a hammer then epoxied into the hole in the nose. The last 1/8" marine ply bit was epoxied in place to help contain the slugs. Now the rest of the 1/64" ply covering can get put onto the fuselage.







The pic shows the balsa plugs cut from the block and model. It shows the slugs removed from the block. Make sure dry wood is used. I pinned the base to the block in lieu of using glue.

[ARUP]

I helped a buddy work on his '74 VW Bug so he reciprocated. We have been changing the tranny and engine on my '59 Bug. Along the way 'shipwright's disease' has crept in and other stuff has been getting done to it. When some needed items arrive we'll get the new engine and tranny hung then I can really get busy on the Charlotte. So far reinforcement of the nose in preparation for mounting the skid was done by adding more ply to it inside. The skid mount holes are marked. Ply was formed for the underside of the center section. Ply was put on the bottom of the fuselage. A fiddly bit of ply was put on the upper nose section of fuselage. I hope to have all the ply on by tomorrow.





Stay tuned!

[ARUP]

All the ply isn't on but at least I'm optimistic!

The power switch was installed and a former is being fabricated to keep the ply from 'oil canning' on the section just aft the nose and ahead of the door. I started to put the ply in place but it wouldn't keep a nice smooth curved shape, i.e., it 'oil canned'. The ply is on the bottom of the center section. It was a bit of a job. The fuse was hung on the board so gravity could assist the glue process!





The last pieces of ply will hopefully go quickly!

[ingrahal]

Good stuff Michael keep it going!